Orthodontics is dentistry's oldest specialty. Unfortunately, in its nearly 100 years of existence, the orthodontic research establishment has never troubled to examine the comparative impact of its various treatment strategies on African-American patients. The research proposed here is designed, therefore, to describe and compare the short- and long-term dental, skeletal, aesthetic, and functional outcomes and efficacy of the two major sets of treatment alternatives commonly employed in the treatment of malocclusion: 1) adolescent fixed-appliance therapy, extraction versus non-extraction, and 2) orthodontics versus surgery in adults. Because of the non-specific character of malocclusion, the elective nature of treatment, and the in-equality of risk among treatments (e.g., surgery and orthodontics), ethical, prospective trials would, of necessity, be severely limited in scope. The present research, therefore, will employ a "retrospective-prospective" design in which great pains are taken to control the types of bias that often compromise case-control studies: selection will be independent of outcome and will employ discriminant analysis to define prognostic sub-groups of known treatment susceptibility - those for whom there is empirical evidence of uncertainty and those who were susceptible only to a single treatment. This approach will serve to control susceptibility bias and thus will mimic many of the most desirable features of prospective, randomized trials. In so doing, it will permit clinically meaningful comparisons between pairs of logical alternatives (e.g., extraction versus non- extraction edgewise or adult orthodontics versus surgery). Additionally this approach will support comparisons with earlier data from white patients (e.g., between European- and African-American sub-groups with comparable facial morphology within a given treatment). Finally, the resulting data will provide insight into the perceived utility to the patient of the various treatment outcomes and the anatomical bases for the esthetic preferences of both European- and African-American adolescents and adults.